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Problem in specifying dependent library files by using MEX switches

Asked by AP on 13 Feb 2013

I am trying to find the instructions for specifying the dependent library files as well as the path for compiling a c++ MEX file. Unfortunately, I wasn't successful and I couldn't get it to work. I don't know how to use:

 COMPFLAGS -I   -l

Could someone please instruct me how to use these switches in Windows for the following case?

 /LIBPATH:"C:\Program Files (x86)\lib\" / l64.lib cr.lib al.lib 

Thanks,

Ahmad

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AP

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2 Answers

Answer by Kaustubha Govind on 13 Feb 2013

You should just need to add them on to the "mex" command. Probably something like:

    >> mex myfile.c -L"C:\Program Files (x86)\lib\" -l l64.lib -l cr.lib -l al.lib 

3 Comments

AP on 13 Feb 2013

Thanks Kaustubha. I also added the path of include files to the MEX command but unfortunately, it still does not work. I also put a spaced after -I and -L but no success.

 >> mex myMEX.cpp -I"C:\Program Files (x86)\FLRecon\Include\" -L"C:\Program Files (x86)\FLRecon\lib\" -l l64.lib -l cr.lib -l al.lib

I get the following error:

 cl : Command line warning D9024 : unrecognized source file type 'Files\MATLAB\R2012b\extern\include -IC:\Program', object file assumed 
DNDEBUG -DMX_COMPAT_32 myMEX.cpp 
c1xx : fatal error C1083: Cannot open source file: 'Files\MATLAB\R2012b\simulink\include /O2 /Oy- /DNDEBUG -DMX_COMPAT_32 myMEX.cpp': No such file or directory 
C:\PROGRA~1\MATLAB\R2012B\BIN\MEX.PL: Error: Compile of 'myMEX.cpp' failed. 
James Tursa on 13 Feb 2013

Sometimes the mex command gets confused with spaces imbedded in strings when using command line syntax. I would try the function syntax instead. E.g. something like:

mex('myMEX.cpp','-I','"C:\Program Files (x86)\FLRecon\Include\"','-L','"C:\Program Files (x86)\FLRecon\lib\"','-l','l64.lib','-l','cr.lib','-l','al.lib')
AP on 13 Feb 2013

Thanks James. Your comment 100% makes sense to me. However, I get the following error:

 C:\PROGRA~1\MATLAB\R2012B\BIN\MEX.PL: Error: 'C:\Program' not found. 
Kaustubha Govind
Answer by Jan Simon on 13 Feb 2013
Edited by Jan Simon on 13 Feb 2013

I had a similar problem with a space in the CFLAGS for Linux: Too add 'CFLAGS="\$CFLAGS -std=c99"' Matlab needs:

mex('CFLAGS="\$CFLAGS', '-std=c99"', ...)

The MEX command is too smart for parsing the non-functional form, so try this:

mex('myfile.c', '-L"C:\Program', 'Files', '(x86)\lib\"',  '-l l64.lib', ...
    '-l cr.lib', '-l al.lib')

This looks as strange as it is. Perhaps the spaces after "-l" are a problem also. I think they should be omitted.

I'm convinced, that MEX has been grown beyond a fair level of usability: Under Windows mex -setup creates a .bat file, which is not called as batch file, but parsed and evaluated in a perl script. Actually starting a compiler is trivial and a handmade M-function would be cleaner and more stable.

2 Comments

AP on 13 Feb 2013

Jan, I tried your solution as following:

 mex('myMEX.cpp','-I"C:\Program','Files','(x86)\FLRecon\include\"','-L"C:\Program','Files','(x86)\FLRecon\lib"','-l lp64.lib','-l cr.lib','-l al.lib')

This is what MATLAB complains about:

 cl : Command line warning D9024 : unrecognized source file type 'Files\MATLAB\R2012b\extern\include -IC:\Program', object file assumed 
DNDEBUG -DMX_COMPAT_32 myMEX.cpp 
c1xx : fatal error C1083: Cannot open source file: 'Files\MATLAB\R2012b\simulink\include /O2 /Oy- /DNDEBUG -DMX_COMPAT_32 myMEX.cpp': No such file or directory 
C:\PROGRA~1\MATLAB\R2012B\BIN\MEX.PL: Error: Compile of 'myMEX.cpp' failed. 
 Error using mex (line 206)
Unable to complete successfully.
Kaustubha Govind on 14 Feb 2013

What about:

mex('myMEX.cpp','-I"C:\Program','Files','(x86)\FLRecon\include\"','-L"C:\Program Files (x86)\FLRecon\lib"','-l lp64.lib','-l cr.lib','-l al.lib')

(I'm wondering if maybe the -L option knows how to deal with the double-quote)

Jan Simon

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